Review Article

Monoamine Oxidases, Oxidative Stress, and Altered Mitochondrial Dynamics in Cardiac Ageing

Figure 1

MAO-A and MAO-B share 73% sequence identity and exhibit overlapping but nonidentical specificities in the oxidation of primary amines. Oxidative deamination of monoamines by the flavoenzyme MAO-A proceeds in two steps: in the first step, binding of the monoamine to the enzyme (E) yields an aldehyde and ammonia by reduction of FAD cofactor; in the second step, the oxidized form of the prosthetic group is restored by the binding of oxygen and the concomitant production of hydrogen peroxide (H2O2). FAD, Flavin adenine dinucleotide.